From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 288C7C4360C for ; Thu, 10 Oct 2019 08:43:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id F2DE821A4A for ; Thu, 10 Oct 2019 08:43:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1570697036; bh=dUfoJ06dfJh7PJfwdIjVvdHLfqLkWv7LXNM+7K9/uJQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=IHdlwQx8gqBXHRyZIYe75+162rr4LIIqwVI5ZoE/zRG3H0fS01TNqi/mU4gDKfYP4 0h6yKU5gSp7TudQXe2kmWwv5nxnDt9BFtfeYV6klBaKYMZCUGAm9u8X5n90qUIfmme W6FNy/7jmqMPUy/6phalzKq6ZY+8YIVQFSe9JjtA= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388829AbfJJIny (ORCPT ); Thu, 10 Oct 2019 04:43:54 -0400 Received: from mail.kernel.org ([198.145.29.99]:48798 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388809AbfJJInw (ORCPT ); Thu, 10 Oct 2019 04:43:52 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 6968B2054F; Thu, 10 Oct 2019 08:43:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1570697031; bh=dUfoJ06dfJh7PJfwdIjVvdHLfqLkWv7LXNM+7K9/uJQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=YWyy48K0zBnLTV9fdE1oygelk75bjkgu7AkalIYRe96P3ZlS/AuXrKsNbNPeHcDeT Nk17MokiIJvg5QoekydbXzD9MspY3dxyE+M4Xix1dd8xna2vzzLN5aSrvMyVXkltXs 9DHRdkgIstBau6nxKRLiNfL+7P6k/dFNRnhhtPEo= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Richard Weinberger , Chao Yu , Gao Xiang Subject: [PATCH 5.3 143/148] staging: erofs: fix an error handling in erofs_readdir() Date: Thu, 10 Oct 2019 10:36:44 +0200 Message-Id: <20191010083620.967516461@linuxfoundation.org> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20191010083609.660878383@linuxfoundation.org> References: <20191010083609.660878383@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Gao Xiang commit acb383f1dcb4f1e79b66d4be3a0b6f519a957b0d upstream. Richard observed a forever loop of erofs_read_raw_page() [1] which can be generated by forcely setting ->u.i_blkaddr to 0xdeadbeef (as my understanding block layer can handle access beyond end of device correctly). After digging into that, it seems the problem is highly related with directories and then I found the root cause is an improper error handling in erofs_readdir(). Let's fix it now. [1] https://lore.kernel.org/r/1163995781.68824.1566084358245.JavaMail.zimbra@nod.at/ Reported-by: Richard Weinberger Fixes: 3aa8ec716e52 ("staging: erofs: add directory operations") Cc: # 4.19+ Reviewed-by: Chao Yu Signed-off-by: Gao Xiang Link: https://lore.kernel.org/r/20190818125457.25906-1-hsiangkao@aol.com [ Gao Xiang: Since earlier kernels don't define EFSCORRUPTED, let's use original error code instead. ] Signed-off-by: Gao Xiang Signed-off-by: Greg Kroah-Hartman --- drivers/staging/erofs/dir.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) --- a/drivers/staging/erofs/dir.c +++ b/drivers/staging/erofs/dir.c @@ -99,8 +99,15 @@ static int erofs_readdir(struct file *f, unsigned int nameoff, maxsize; dentry_page = read_mapping_page(mapping, i, NULL); - if (IS_ERR(dentry_page)) - continue; + if (dentry_page == ERR_PTR(-ENOMEM)) { + err = -ENOMEM; + break; + } else if (IS_ERR(dentry_page)) { + errln("fail to readdir of logical block %u of nid %llu", + i, EROFS_V(dir)->nid); + err = PTR_ERR(dentry_page); + break; + } de = (struct erofs_dirent *)kmap(dentry_page);